The present invention relates generally to door assemblies and, more particularly, to overhead sliding door assemblies and associated interior paneling for airplanes.
Overhead sliding passenger doors are commonly employed in the main passenger doorways of commercial airliners. Such a door is opened by raising it upwardly over the doorway on tracks affixed to the inside of fuselage. The raised door is thereby stowed out of the way in an overhead position. The door is ordinarily passed through an opening in the cabin ceiling and stowed out of sight in an overhead space above the ceiling.
The overhead sliding door is particularly suited to an airliner because the curved contour of the fuselage conveniently accommodates the similarly curved door, enabling the door to fit closely against the inside of the fuselage during opening and closing. As a result, the primary advantage over a conventional hinged door is that the overhead sliding door does not have to be swung open inwardly into the occasionally crowded passenger cabin area, or swung outwardly in an awkward manner by an operator standing inside the airplane. Examples of overhead sliding door assemblies are disclosed in U.S. Pat. Nos. 4,106,729 to Bergman et al. and 3,802,125 to Baker, which are hereby incorporated by reference. Although the practical advantages of overhead sliding doors are well recognized in the aircraft industry, they pose particular design problems in connection with the placing of interior wall and ceiling paneling above the doorway, as discussed further below.
For example, there is the problem of providing a suitable closure member for the ceiling opening over the doorway. Such a closure member is necessary for purposes of apearance and air circulation control when the door is down, and must be removable to permit the door to pass through the ceiling opening. Further, the closure member must be movable conjointly with the door assembly so that the operator does not have to move the ceiling closure member each time the door is opened and closed.
Further, in the door assembly disclosed in the above-referenced patent to Bergman et al., there is affixed to the lower inside of the door an escape slide enclosed in a rigid container. In an emergency, the escape slide can be deployed outwardly through the doorway and inflated to form a semirigid escape slide extending to the ground. The folded escape slide and its container are somewhat bulky and extend inwardly into the cabin area approximately eight inches from the inside of the door. This inward protrusion of the escape slide container, together with the inward movement of the entire door that is necessary for it to clear the doorway before sliding upwardly on its tracks, requires that the ceiling opening be of substantial size. This further accentuates the need for a removable closure member and also makes it desirable to have a means for closing the ceiling opening when the door is raised, as well as when the door is lowered.
Additionally, in airplanes wherein the top of the doorway is lower than the cabin ceiling, there is a need for a presentable, removable interior panel to cover the fuselage wall above the doorway. This portion of the fuselage wall ordinarily includes door tracks and various mechanical linkages that would otherwise be visible with the door in the closed position and would be unsightly in a passenger airliner. In order to accommodate upward movement of the door, however, such a panel must be movable out of the way when the door is raised. One solution to this problem would be to make such a panel integral with the door, such that the panel travels upwardly with the door when the door is raised. This approach is not feasible in certain cases, however, because the combined height of the door and such an integral overhead panel is too great for the door to be stowed in the overhead space above the cabin ceiling, particularly in view of certain additional problems discussed below.
Another particular problem to which the present invention is directed is the stowage of an overhead sliding door in the limited overhead space available in medium-sized airliners having fuselages of relatively small diameter. The overhead stowage space in such airliners, for example a Boeing 767 airplane, is crowded with control cables, ducting, electrical wiring, lights and other items. Under such conditions, it has not been feasible to provide a simple trap door in the ceiling through which the door and its associated interior panels can be raised, as has been done in larger airliners having a larger overhead stowage space.
Also, in airplanes of relatively small fuselage diameter it has proven difficult to provide a pair of full-length overhead sliding doors disposed in the sides of the fuselage opposite one another, since there is insufficient room in the overhead compartment for both doors and their associated paneling to be raised at once without interfering with one another. A simple alternative in such a case would be to offset the doors along the fuselage. This solution is not altogether satisfactory, however, because it is desirable for the doors to be symmetrically positioned on opposite sides of the airplane to accommodate standardized passenger boarding facilities, and because of other design considerations.
Accordingly, it is the object and purpose of the present invention to provide a combined door and interior cabin panel assembly that includes a presentable panel closure member for the overhead opening of the cabin ceiling when the door is in its closed position, and which also allows the door to be opened inwardly and raised upwardly through the opening to a stowed position above the cabin ceiling. More particularly, it is an object to provide such an assembly wherein a set of foldable cabin panels are coupled to the door and adapted to fold upwardly out of the way as the door is opened.
It is also an object to provide an overhead sliding door and panel assembly that includes a movable interior fuselage panel that covers the fuselage wall above the doorway when the door is closed, and which is movable upwardly out of the way when the door is raised.
It is another object of the present invention to achieve the foregoing objects and also provide an overhead sliding door and interior panel assembly that operates to form a closure member in the ceiling opening when the door is raised to its overhead stowed position.
It is yet another object to provide an overhead sliding door and interior panel assembly particularly adapted to a relatively small commercial airliner having limited overhead stowage space. In particular, it is an object to provide a full-length door assembly and associated interior paneling that can be stowed overhead in a sufficiently compact condition to permit another similar door assembly to be located on the opposite side of the fuselage, and wherein both doors may be raised to the open position simultaneously.